Toshiki Endo

Fatal subarachnoid hemorrhage, with brainstem and cerebellar infarction, caused by Aspergillus infection after cerebral aneurysm surgery: case report.

OBJECTIVE AND IMPORTANCE Intracranial aspergillosis has been reported to cause subarachnoid hemorrhage (SAH) attributable to ruptured mycotic aneurysms. We describe a case of Aspergillus arteritis that caused SAH without aneurysm formation, followed by successive brainstem and cerebellar infarction. CLINICAL PRESENTATION A 50-year-old woman experienced a sudden onset of headache. Computed tomography demonstrated SAH. After angiography revealed an aneurysm of the anterior communicating artery, a complete neck-clipping operation was performed, without neurological deterioration. However, the patient experienced another episode of SAH on the 26th postoperative day. INTERVENTION We repeated the craniotomy and confirmed that the clip was still intact. A second angiographic evaluation did not reveal an aneurysm or any other cause of hemorrhage. On the 30th postoperative day, magnetic resonance imaging demonstrated cerebellar infarction in the territory of the anteroinferior cerebellar artery. The patient died on the 40th postoperative day, after another episode of SAH and progressive cerebellar and brainstem infarction. The postmortem examination revealed destruction of the basilar artery and occlusion of the basilar and vertebral arteries attributable to Aspergillus arteritis. CONCLUSION When a patient presents with SAH of unknown origin followed by cerebral infarction, Aspergillus arteritis should be included in the differential diagnosis. Earlier recognition of this fungal infection improves the prognosis.

Neurohypophyseal germinoma histologically misidentified as granulomatous hypophysitis.

Summary. We report a case of neurohypophyseal germinoma appearing as predominantly granulomatous reaction in the first histological examination. A 12-year-old boy presented with diabetes insipidus, panhypopituitarism, and bitemporal hemianopsia. Transsphenoidal exploration for the intrasellar mass lesion extending to the suprasellar region was performed in May 1999. Histological examination revealed granulomatous hypophysitis and corticosteroid therapy was initiated. Six months later, the lesion relapsed despite corticosteroid therapy. Subtotal removal of the lesion was performed via an anterior interhemispheric approach in December 1999. Histological examination revealed typical germinoma. Subsequently, the patient underwent irradiation of 20 Gy to the tumour site and 24 Gy to the whole brain. Magnetic resonance imaging confirmed tumour remission. We must consider the possibility of neurohypophyseal germinoma in patients with granulomatous hypophysitis which does not respond to corticosteroid therapy, and perform re-exploration for more specimens to achieve the correct diagnosis.

Axial loading during magnetic resonance imaging in patients with lumbar spinal canal stenosis: does it reproduce the positional change of the dural sac detected by upright myelography?

Study Design. We compared the sizes of the dural sac among conventional magnetic resonance imaging (MRI), axial loaded MRI, and upright myelography in patients with lumbar spinal canal stenosis (LSCS). Objective. To determine whether axial loaded MRI can demonstrate similar positional changes of the dural sac size as were detected by upright myelography in LSCS. Summary of Background Data. In patients with LSCS, constriction of the dural sac is worsened and symptoms are aggravated during standing or walking. To disclose such positional changes, upright myelography has been widely used. Recently, axial loaded MRI, which can simulate a standing position, has been developed. However, there has been no study to compare the dural sac size between axial loaded MRI and upright myelography. Methods. Forty-four patients underwent conventional MRI, axial loaded MRI, and myelography. Transverse and anteroposterior diameters and the cross-sectional areas of the dural sac from L2–L3 to L5–S1 were compared. Pearson correlations of the diameters between the MRIs and the myelograms were analyzed. On the basis of the myelograms, all disc levels were divided into severe and nonsevere constriction groups. In each group, the diameters and the cross-sectional areas were compared. Sensitivity and specificity to detect severe constriction were calculated for the conventional and axial loaded MRI. Results. Transverse and anteroposterior diameters at L4–L5 in the axial loaded MRI and myelogram were significantly smaller than those observed in the conventional MRI (P < 0.001). Cross-sectional areas in the axial loaded MRI were significantly smaller than those in the conventional MRI at L2–L3, L3–L4, and L4–L5 (P < 0.001). Between the axial loaded MRI and the myelography, Pearson correlation coefficients of the transverse and anteroposterior diameters were 0.85 and 0.87, respectively (P < 0.001), which were higher than those for conventional MRI. Reductions of the dural sac sizes in the axial loaded MRI were more evident in the severe constriction group. The axial loaded MRI detected severe constriction with a higher sensitivity (96.4%) and specificity (98.2%) than the conventional MRI. Conclusion. The axial loaded MRI demonstrated a significant reduction in the dural sac size and significant correlations of the dural sac diameters with the upright myelogram. Furthermore, the axial loaded MRI had higher sensitivity and specificity than the conventional MRI for detecting the severe constriction observed in the myelogram. Therefore, the axial loaded MRI can be used to represent positional changes of the dural sac size detected by the upright myelography in patients with LSCS.

Effects of sevoflurane on electrocorticography in patients with intractable temporal lobe epilepsy.

Fentanyl-droperidol technique is the choice for epilepsy surgery. It requires intraoperative electrocorticography (ECoG), but a large dose of fentanyl is needed for this technique. On the other hand, sevoflurane reportedly may be beneficial for intraoperative ECoG. To reveal whether the combined technique with fentanyl and sevoflurane is beneficial for epilepsy surgery, we investigated ECoG in 10 patients with intractable temporal lobe epilepsy without sevoflurane, with 0.5 minimum alveolar concentration (MAC) sevoflurane, and with 1.5 MAC sevoflurane under fentanyl-based anesthesia. The mean number of spikes for 1 minute decreased from 38.3 to 14.1 after 1.5 MAC sevoflurane was induced, which was statistically significant (P < .05). Our results showed that balanced technique with neurolepto-analgesia (NLA) and sevoflurane is not suitable for epilepsy surgery requiring intraoperative ECoG. When epilepsy surgeries are performed under sevoflurane anesthesia, it is important to consider that sevoflurane may suppress electric activities when it is used with other anesthetic agents.

Concurrent dural and perimedullary arteriovenous fistulas at the craniocervical junction: case series with special reference to angioarchitecture

OBJECT Dural arteriovenous fistulas (DAVFs) and perimedullary arteriovenous fistulas (PAVFs) are uncommonly associated in the craniocervical junction. The purpose of this study was to describe the clinical and angiographic characteristics of such concurrent lesions. METHODS Authors reviewed 9 cases with a coexistent DAVF and PAVF at the craniocervical junction. Clinical presentation, angiographic characteristics, intraoperative findings, and treatment outcomes were assessed. RESULTS All patients (male/female ratio 5:4; mean age 66.3 years) presented with subarachnoid hemorrhage. Angiography revealed that 8 patients had both a DAVF and PAVF on the same side, whereas 1 patient had 3 arteriovenous fistulas, 1 DAVF, and 1 PAVF on the right side and 1 DAVF on the left side. All of the fistulas shared dilated perimedullary veins (anterior spinal vein, 7 cases; anterolateral spinal vein, 2 cases) as a main drainage route. The shared drainage route was rostrally directed in 8 of 9 cases. Eight patients exhibited an arterial aneurysm on the distal side of the feeding arteries to the PAVF, and the aneurysm in each case was intraoperatively confirmed as a bleeding point. One patient had ruptured venous ectasia at the perimedullary fistulous point. All patients underwent direct surgery via a posterolateral approach. No recurrence was observed in the 4 patients who underwent postoperative angiography, and no rebleeding event was recorded among any of the 9 patients during the follow-up period (mean 38.4 months). CONCLUSIONS The similarity of the angioarchitecture and the close anatomical relationship between DAVF and PAVF at the craniocervical junction suggested that these lesions are pathogenetically linked. The pathophysiological mechanism and anatomical features of these lesions represent a unique vascular anomaly that should be recognized angiographically to plan a therapeutic strategy.

Long-term Outcome of Cervical and Thoracolumbar Dural Arteriovenous Fistulas With Emphasis on Sensory Disturbance and Neuropathic Pain

BACKGROUND Clinical features and prognosis of sensory disturbance in spinal dural arteriovenous fistula (SDAVF) have not been well documented. Here we report long-term outcomes and detailed sensory evaluations of surgically treated SDAVF, including 14 patients with the craniocervical fistulas. METHODS Thirty-four consecutive patients with SDAVF treated at our institute during a period of 14 years were reviewed (mean age, 64.6 years; 67.6% men). Fistulas were located at the craniocervical junction in 14 patients (CC group) and in the thoracolumbar spine in 20 patients (TL group). In the CC group, six patients presented with subarachnoid hemorrhage. Fistulas were found incidentally in seven patients. One patient in the CC group and all patients in the TL group presented with progressive myelopathy. Most patients underwent microsurgery either alone (30 patients) or combined with embolization (3 patients). One patient was treated by embolization only. The follow-up ranged from 12 to 145 months (mean, 57 months). RESULTS All but one patient in the CC group had excellent surgical outcome. Most patients in the TL group stabilized or improved neurologically. Shorter duration before treatment indicated better gait recovery. Important, a few patients in the TL group suffered worsening or development of new pain, as well as lesser degree of improvement in gait and micturition. Spinal cord atrophy was correlated with clinical deterioration. CONCLUSIONS In craniocervical SDAVF, surgical treatment provides favorable long-term outcomes without risk of recurrence. In the thoracolumbar SDAVF, irreversible structural changes, such as spinal cord atrophy, may lead to poor recovery. Early diagnosis and treatment are thus warranted.

Surgical treatment of spinal intradural arachnoid cysts using endoscopy

OBJECT Spinal intradural arachnoid cysts are a rare cause of spinal cord compression. Since 2000, the authors have treated patients using 2- or 3-level hemilaminectomy or laminectomy followed by partial cyst wall resection as well as endoscopic inspection and fenestration of the cyst wall. They evaluated the usefulness and reliability of endoscopic treatment for this clinical entity based on long-term follow-up results. METHODS Between 1997 and 2003, 11 patients (3 males and 8 females) with spinal intradural arachnoid cysts were treated, and the authors conducted a retrospective review of these cases. Before 2000, 5 patients were surgically treated without the use of endoscopic techniques. During that time, more than 4 levels of hemilaminectomy were performed to expose and remove cyst walls that extended longitudinally over the spinal axis. Beginning in 2000, endoscopy was used in all 6 cases. Up to 3 levels of hemilaminectomy or 2 levels of laminectomy were performed, and the cyst wall was resected through the bone window. An endoscope was inserted into the cyst cavity and moved in the cranial and caudal direction to fenestrate the cyst wall, resulting in communication of the cyst cavity with the subarachnoid space. RESULTS Postoperatively, the neurological symptoms of all patients improved. During long-term follow-up (mean 114.8 months), none of the patients treated with or without endoscopy experienced recurrent cyst formation. CONCLUSIONS Endoscopic techniques allow neurosurgeons to treat spinal intradural arachnoid cysts less invasively than with standard surgical approaches. Although the number of cases reviewed in this report is small, the data suggest that the use of endoscopy can be an important option in the surgical treatment of spinal arachnoid cysts.

Malignant intracranial epithelioid hemangioendothelioma presumably originating from the lung: case report.

AbstractObjective and importance: Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor that presents histological features and biological behavior of low-grade malignancy. The authors report a case of malignant intracranial EHE, in which surgical excisions and additional immuno-chemotherapy were ineffective. Emphasis is placed on the histological features of this rare tumor and its potential for malignancy. Clinical presentation: A 69-year old male presented with paresis of the right arm. Magnetic resonance imaging revealed intracranial multiple lesions in the right temporal and parietal and left frontal lobes. Chest radiography revealed a mass lesion occupying the lower lobe of the left lung that had been followed as old tuberculosis since it had not changed in size for as long as 5 years. Intervention: We performed craniotomy and excised tumors. Histological examination demonstrated that the excised tumors had the features of EHE. Further intracranial recurrence after the excision of the tumors necessitated adjuvant treatment with interferon alpha-2b. However, the patient continued to deteriorate and died 3 months later. Postmortem study disclosed the tumor cells existing in the left lung, pleura, ribs, intercostal tissues and diaphragm. Other organs including liver, bone, and skin were free from tumor invasion, which indicated that the malignant EHE originated from the left lung and metastasized to the brain. Conclusion: To the authors knowledge, no case of malignant EHE that simultaneously involves the central nervous system and the lung has been previously reported. An extensive inspection for involvement of other organs is recommended after recognizing an intracranial EHE.

Use of microscope-integrated near-infrared indocyanine green videoangiography in the surgical treatment of intramedullary cavernous malformations: report of 8 cases.

OBJECT The characteristics and efficacy of indocyanine green (ICG) videoangiography in cavernous malformation (CM) have not been fully elucidated. The purpose of this paper is to examine the potential utility of ICG videoangiography in the surgical treatment of intramedullary CMs. METHODS The authors conducted a retrospective review of 8 cases involving 5 men and 3 women who had undergone surgery for intramedullary CM between January 2008 and July 2011. All patients were evaluated by means of MRI. The MRI findings and clinical history in all cases suggested intramedullary CM as a preoperative diagnosis. In 2 of 8 cases, dilated venous structures associated with CMs were demonstrated. In one of these cases, there were coexisting extramedullary CMs. Intraoperatively, ICG fluorescence was observed for 5 minutes using microscope-integrated videoangiography. RESULTS In all 8 cases, intra- and extramedullary CMs were seen as avascular areas on ICG videoangiography. Indocyanine green videoangiography helped surgeons to localize and predict margins of the lesions before performing myelotomy. Importantly, in the cases with associated venous anomalies, ICG videoangiography was useful in delineating and preserving the venous structures. In extramedullary CMs located dorsal to the spinal cord, gradual ICG infiltration was seen, starting at 110 seconds and maximal at 210 seconds after injection. Postoperative MRI confirmed total removal of the lesions in all cases, and subsequent recovery of all patients was uneventful. CONCLUSIONS Indocyanine green videoangiography provided useful information with regard to the detection of lesion margins by demonstrating intramedullary CMs as avascular areas. In cases associated with venous anomalies, ICG contributed to safe and complete removal of the CMs by visualizing the venous structure. In extramedullary CMs, ICG videoangiography demonstrated the characteristic of slow blood flow within CMs.

Cortical Changes Following Spinal Cord Injury with Emphasis on the Nogo Signaling System

After spinal cord injury, structural as well as functional modifications occur in the adult CNS. Sites of plastic changes include the injured spinal cord itself as well as cortical and subcortical structures. Previously, cortical reorganization in response to sensory deprivation has mainly been studied using peripheral nerve injury models, and has led to a degree of understanding of mechanisms underlying reorganization and plastic changes. Deprivation or damage-induced CNS plasticity is not always beneficial for patients, and may underlie the development of conditions such as neuropathic pain and phantom sensations. Therefore, efforts not only to enhance, but also to control the capacity of plastic changes in the CNS, are of clinical relevance. Novel methods to stimulate plasticity as well as to monitor it, such as transcranial magnetic stimulation and functional magnetic resonance imaging, respectively, may be useful in diverse clinical situations such as spinal cord injury and stroke. Here, human and animal studies of spinal cord injury are reviewed, with special emphasis on the contribution of the Nogo signaling system to cortical plasticity.